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$300,000 Mortgage at 4.5% for 30 Years

Monthly payment breakdown for a fixed-rate 30-year home loan.

Monthly Payment

$1,520

Principal: $300,000 · Rate: 4.5%

Item Amount
Loan Principal $300,000
Total Interest (30 years) $247,220
Total Paid $547,220

Amortization Schedule (Yearly Summary)

How your payments are split between principal and interest each year.

Year Principal Paid Interest Paid Remaining Balance
1 $4,840 $13,401 $295,160
2 $5,062 $13,179 $290,098
3 $5,295 $12,946 $284,804
4 $5,538 $12,703 $279,266
5 $5,792 $12,448 $273,474
6 $6,058 $12,182 $267,415
7 $6,337 $11,904 $261,079
8 $6,628 $11,613 $254,451
9 $6,932 $11,308 $247,519
10 $7,251 $10,990 $240,268
30 $17,804 $437 $0

Rate Comparison — $300K Loan

Rate Monthly Payment Total Interest Total Paid
4% $1,432 $215,609 $515,609
5% $1,610 $279,767 $579,767
4.5% (current) $1,520 $247,220 $547,220

Understanding a $300K Mortgage at 4.5%

A $300,000 fixed-rate mortgage at 4.5% interest over 30 years results in a monthly payment of $1,520. Over the full loan term, you will pay $247,220 in interest — roughly 0.8× the original loan amount.

In the early years, most of your payment goes toward interest. By year 10, approximately $7,251 of your annual payments go to principal and $10,990 to interest. Over time, the balance shifts as the principal portion grows.

Frequently Asked Questions

What is the monthly payment on a $300,000 mortgage at 4.5%?

The monthly payment on a $300,000 mortgage at 4.5% interest for 30 years is $1,520. Over the life of the loan, you will pay $247,220 in interest, for a total of $547,220.

How much total interest will I pay on a $300,000 mortgage at 4.5%?

On a $300,000 mortgage at 4.5% over 30 years, you will pay $247,220 in total interest. This means you pay roughly 0.8x the original loan amount in interest alone.

How does 4.5% compare to other mortgage rates?

At 4.5% on a $300,000 30-year loan, the monthly payment is $1,520. A 0.5% rate decrease would save approximately $88/month, while a 0.5% increase would add about $90/month.

How This Is Calculated

This page uses the standard fixed-rate amortization formula to compute the monthly mortgage payment:

M = P × [r(1+r)n] / [(1+r)n − 1]

Where P = $300,000 (loan principal), r = 0.003750 (monthly interest rate = 4.5% ÷ 12), and n = 360 (total payments = 30 years × 12 months).

Standard amortization formula. Assumes fixed-rate loan, no PMI, taxes, or insurance.

Explore Other Rates for $300K Loan

Explore Other Loan Amounts at 4.5%

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⚠️ Estimates only. Actual mortgage costs may include PMI, property tax, insurance, and HOA fees. Consult a lender for precise figures.